The present invention relates to an electric submersible pump assembly and, more particularly, to assemblies and methods for reducing gas content of produced fluids.
Commercially viable levels of production from hydrocarbon wells may require assistance in lifting produced fluids to the surface. Formation pressure may be inadequate to drive produced fluids upward to the surface. In deeper wells, hydrostatic head may act downwardly, inhibiting flow to the surface.
Frequently, an underground pump is used to force fluids toward the surface. An electric submersible pump (ESP) may be installed in a lower portion of the wellbore. In wells with high volumes of gas, gas separators may also be included, to separate gas from the rest of the produced fluids. The gas may be separated in a mechanical or static separator and vented to the annulus. The remainder of the produced fluid may enter the ESP, which may pump it to the surface via production tubing.
In wells producing gas, the ESP may be used to pump water out of the wellbore to maintain the flow of methane gas. In this instance, the water is pumped up production tubing, while the methane gas flows up the annulus between the production tubing and the wellbore. However, some methane gas entrained in the water will be pumped by the pump. Wells that are particularly “gassy” may experience a significant amount of the methane gas passing through the pump, which may cause gas lock, resulting in costly and time-consuming shutdowns.